1. Field of the Invention
The invention concerns the field of loads or charges releasable from an aircraft to which they are fixed and, in particular, the keel beam safety device which prevents the activating of the charge when it is hooked beneath the aircraft.
2. Description of the Prior Art
Most releasable charges, such as bombs, are fitted out with a number of systems for the control or activation of fuses which have to be activated, after release, at a determined moment on the trajectory of the charge. Permission to activate is provided, in most cases, by a releasable safety device, also called an "RS", formed by a flexible or semi-rigid cable, connected by one of its ends to the aircraft keel beam, that is, to the metallic part fixed to the structure of the aircraft to which the charges are hooked and, by its other end, to the charge to be released or, in certain cases, to the fuse of the bomb.
Any untimely tensile force exerted on this cable, either when it is being positioned beneath the aircraft or during the flight on which the charge is carried beneath the aircraft, for example if it is struck by a winged creature, may cause the unexpected, partial or total activation of the charge that has to be released or of the bomb fuse.
The keel beam safety devices may be either electrical or mechanical. In the latter case, which corresponds to the field of the invention described, the safety device partially or totally prevents the motion of the RS cable when the bomb is hooked beneath the aircraft: these devices, in their application, should enable the following simultaneously:
hooking the "RS" to any point of the aircraft keel beam; PA1 operation when the distance between the upper part of the onboard charge and the keel beam of the aircraft is between a few millimiters and a few centimeters; PA1 preventing the activation of two fuses in one and the same charge. PA1 the general rigidity of the charge; PA1 its performance characteristics as a fragment generator; PA1 the ballistics of the charge if the devices are external.
They should furthermore occupy the most restricted volume possible to avoid adversely affecting: